1. Technical Field
The disclosure relates to an inkjet printer configured to perform printing by ejecting ink from an inkjet head onto continuous paper.
2. Related Art
Japanese Patent Application Publication No. 2011-189748 proposes an inkjet printer which performs printing by unwinding a sheet of long continuous paper from a sheet roll and ejecting inks from an inkjet head onto the sheet while conveying the sheet.
In the inkjet printer described above, the behavior of the sheet is unstable during acceleration after start of sheet conveyance, and the sheet under the inkjet head sometimes moves up and down. Accordingly, if the printing is performed by ejecting the inks from the inkjet head during the acceleration of the sheet, landing positions of the inks deviate from their proper positions and print quality decreases in some cases.
In view of this, some inkjet printer is configured to suspend printing during the acceleration of the sheet and, after the sheet reaches a predetermined printing conveyance speed, perform the printing by ejecting the inks from the inkjet head while conveying the sheet constantly at the printing conveyance speed.
In this case, a portion of the sheet which is conveyed under the inkjet head during the acceleration to reach the printing conveyance speed from the start of conveyance is not used and is wasted. This portion which is wasted is referred to as wasted portion. This wasted portion becomes wasted paper when cut from the sheet.
Reducing tension applied to the sheet during the acceleration reduces load on a conveyer, and this can reduce acceleration time required for the sheet to reach the printing conveyance speed. The wasted portion can be thereby reduced.